(u-7)^2-50=0 where u is a real number.?
2009-06-13 7:41 am
is anyone good at this? I there is more than one solution, sep. w/ commas. Please help me : )
回答 (5)
2009-06-13 7:47 am
✔ 最佳答案
(u-7)^2-50=0 Add 50: (u-7)^2 = 50
Sq Roots: u-7 = (+ or -) sqrt(50)
Add 7: u = 7 (+ or -) sqrt(50)
Since sqrt(50) = sqrt(25 * 2) = 5 sqrt(2), we can rewrite the solutions:
x = 7 + 2 sqrt(5), 7 - 2 sqrt(5).
2009-06-13 5:03 pm
(u - 7)^2 - 50 = 0
(u - 7)^2 = 50
u - 7 = 屉50
u - 7 = 屉(5^2 * 2)
u - 7 = ±5â2
u = 7 ±5â2
(u - 7)^2 = 50
u - 7 = 屉50
u - 7 = 屉(5^2 * 2)
u - 7 = ±5â2
u = 7 ±5â2
2009-06-13 2:55 pm
7+/-5sqrt2
2009-06-13 2:49 pm
{{u == 7 - 5 Sqrt[2]}, {u == 7 + 5 Sqrt[2]}}
2009-06-13 3:04 pm
Its either prime or you will have to use the perfect square formula
(u-7)^2 becomes (u-7)(u-7) which equals u^2-14u+49
therefore you have u^2-14u+49-50=0 combine 49-50=-1
u^2-14u-1 is not factorable
(u-7)^2 becomes (u-7)(u-7) which equals u^2-14u+49
therefore you have u^2-14u+49-50=0 combine 49-50=-1
u^2-14u-1 is not factorable
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